I'm not too familiar with the rear differential. As posted in other threads I had my rear differential housing replaced last year.

Recently I had a low "drone" from the differential. Took it in Thursday; picked it up today. Dealer replaced my pinion bearings due to scoring.

What would cause the pinion bearings to score? Is this common? Should I expect this type of maintenance ongoing (hope not I'm coming close to the end of the warranty)?

Truck has been driven like a commuter car the past year; towing only minimal loads (6,000 lbs 2-3x in the past year for a total of 500 miles).

Any insight would be appreciated.

2006 LBZ Crewcab 4x4.

Mike S.

Hello- shop maybe got pinion bearings too tight when they replaced axle casting !

If it was droning the pinnion shaft nut probably came loose. The nut should be installed with thread locker. My truck had the same problem and I just had the rear end rebuilt. It is possible they got them too tight but due to the fact that you have driven it a year and didn't have other problems I would guess the nut backed off.

Old Man/Blue Max:

Thank you very much for the insights! When the replaced my rear diff last year I questioned how they could have done it so quick. I assumed this bearing score was the result of a lack of attention to detail. From your responses (either too tight or the nut wiggling loose) it seems they did a rush job. Confirms my hunch.

Thank you both for your insights! Appreciated and you guys are the reason this site is so valuable/awesome! Thanks again!